Products

Japan Engine Corporation (J-ENG)

UEC-LSJA ammonia engine

Ammonia dual-fuel UE engine; the first 7UEC50LSJA-HPSCR completed full-scale testing in 2025 with over 90% GHG reduction.

The LSJA is J-ENG's ammonia dual-fuel version of the UE engine. After single-cylinder testing from 2023 to 2024, the first full-scale commercial engine, a 7-cylinder 50 cm bore 7UEC50LSJA with high-pressure SCR, ran about 700 test hours from April to September 2025, achieving roughly 3 ppm N2O at 95% ammonia co-firing and over 90% GHG reduction. It was delivered in October 2025 and won Marine Engineering of the Year 2025. A 60 cm bore variant is also listed.

Specifications

Bore mm
500, 600
Cylinders
7 (first engine)
Fuels
ammonia, MGO

Listed under

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